Hip fractures are a major health and economic problem for the elderly and our society as a whole. Treatment for hip fractures includes surgery and prolonged periods of bed rest, both of which expose patients to significant complications such as infection and pneumonia. Recovery, either complicated or uncomplicated, can result in significant disturbance in the life of a patient and his/her family, and substantial medical costs. After hip fracture, many elderly patients may need to further restrict their activities, need a "walker," be confined to a wheelchair and often require full or part-time assistance. As a significant causes of disability and death in the elderly, the number and importance of hip fractures will surely increase as the number and percentage of the elderly increases.
In 1990 it was estimated that the number of hip fractures in persons over the age of 50 would increase from 238,000 to 512,000 per year by 2040 with an increase in cost from $7.2 billion to $16 billion per year This was based on an average cost of $29,800 per hip in 1984 dollars, assuming no change in the average cost and a 3% to 5% increase for inflation. No value can be placed on the pain and suffering of the injured and the burden on family and friends who care for them.
According to the "Tufts University Diet & Nutrition Letter" Vol. 12 No. 4, June 1994, "...As many as 20 percent of all people who suffer a hip fracture die within a year, usually because of complications like pneumonia or blood clots in the lung that are related to either the fracture itself, surgery to heal the break, or being confined to bed..."
There has been little progress in the prevention of hip fractures despite our growing knowledge about contributing factors. Diet, calcium supplements and exercise, which help strengthen elderly bones may be helpful, but probably will not significantly decrease the incidence of hip fractures.
The hip joint is a ball and socket (enarthrodial) joint formed by the cup-shaped cavity in the pelvic bone (acetabulum) and the ball-shaped head of the upper leg bone (femur). The lateral hip and particularly the area of the trochanter, an area of bone which protrudes outwardly from the femur just below the hip joint, is particularly vulnerable to injury and fracture. This vulnerability results from the lateral position and relatively thin layer of overlying muscle and fat.
The protective device is a marked improvement over the design and function of prior art for a number of significant reasons. These reasons and other unique features of the invention will be fully discussed.
Prior art for garments to protect the hip do not combine protection, comfort and ease of use. Girdle-like undergarments, whether essentially pads or inflatable bags, are difficult to put on and take off, and may create significant other problems for elderly people. Examples of such devices are U.S. Pat. Nos. 4,737,994; 5,297,293, 4,977,623. If such garments are not completely moisture resistant they will soon become dirty and probably soiled with urine and feces. The result is unsanitary, unpleasant, unsightly and uncomfortable for patients and attendants. Additionally, such garments, which by their very nature must fit snugly, can compromise blood circulation and could contribute to the development of decubitus ulcers, a dangerous problem with significant morbidity and even mortality in elderly, immobile and bedridden patients.
Other prior art is not designed for use in the elderly and does not contain important design features found in this protective device. Examples of this are U.S. Pat. No. 4,825,469 which in all its embodiments is designed to protect motorcycle riders, is too large and wide for use by the elderly, will restrict body movement and activities of daily living, employs an external source of compressed gas which is connected to the invention by a tube and is inflated mechanically by a string when the rider is thrown from the motorcycle. U.S. Pat. No. 4,059,852 for cyclists and 4,089,065 for mountain/rock climbing, hang gliding, race car driving, piloting and white water canoeing are full body devices, manually inflated and clearly not "automatic" or intended for use by the elderly. U.S. Pat No. 4,984,821 describes a gas expansion safety cloth for motorcyclists which is fired by a pull string and has external gas storage and discharge device which inflates the cloth when the wearer is thrown from the cycle. It is clearly not for use in the elderly. U.S. Pat. No. 4,637,074 is intended for use in automobile accidents, is too large for use by the elderly, and has external sensing, firing and compressed gas cartridge. U.S. Pat. No. 3,921,944 is bulky, not easily put on, removed or worn, and is inappropriate for use by the elderly. U.S. Pat. No. 4,089,065, particularly suitable for hang-gliding or parachuting, is not intended for the elderly because it is a full jacket and/or pants garment, bulky, intended to be worn only during those high risk activities and is manually activated.
In the development of this protective device it was most logical to look towards the airbag, also known as the Safety Air Cushion (SAC). This practical device was invented and designed to protect drivers and passengers in automobile accidents. Examples of airbags and airbag inflation devices are found in U.S. Pat. Nos. 3,430,979, which uses pressurized gas for inflation; 4,178,016 and 4,243,248, which both use pyrotechnic devices for inflation.
The protective device, in contrast to prior art, does not depend on internal fastening devices which cannot be visually inspected, can fail to align properly after deflation (thus compromising function on the next inflation) and may wear out at an accelerated rate. An example of such design is U.S. Pat. No. 4,089,065.
In contrast, the invention, when uninflated, uses very thin external Velcro-type straps to keep the pleats in place. In other embodiments the invention may keep the pleats in place with snaps, which will easily separate on inflation.
The invention, in contrast to prior art, does not depend on multiple separate inflatable chambers for coverage of the body areas to be protected. Such devices may not fully protect all the areas if one of the inflatable air chambers fails to inflate and fully expand. This is because the inflation and movement of any one air chamber to cover an area of the body is dependent upon the full inflation and movement of the adjacent chambers. This is particularly true for the uppermost and lowermost body areas protected by the device. U.S. Pat. No. 4,825,469 is an example of such a device.
In contrast, the protective device is comprised of an airbag or airbags with portions folded into several pleats contained within the device, which on inflation expand out of the protective device to cover the entire body area to be protected. Inflation and expansion are not hindered by internal attachments between the pleats.
The protective device described in this application fills an important need in preventive medical care for the elderly. The invention, in this embodiment, for the first time provides a simple, comfortable, easily worn self-contained, automatic device which provides maximum protection to the hip, pelvis, buttocks and coccyx areas in falls and does not interfere with activities of daily living.